Portable hydraulic lift truck



Aug. 29, 1967 A. D. KlRLl-N 'PORTABLE HYDRAULIC LIFTTRUCK 2 Sheets-Sheetl Filed Dec. 20, 1965 w f. /Z m J2 la@ i /J w Aug. 29, 1967 Filed Dec.20, 1965 A. D. KIRLIN PORTABLE HYDRAULIC LIFT TRUCK 2 Sheets-Sheet 2United States Patent O 3,338,586 PQRTABLE HYDRAULIC LIFT TRUCK Albert D.Kil-lin, Pocatello, Idaho, assignor to Industrial Manufacturing Company,Pocatello, Idaho, a corporation of Idaho Filed Dec. 20, 1965, Ser. No.514,970 9 Claims. (Cl. 280-5.3)

This invention relates to a lift truck and more specifically to aportable hydraulic lift truck.

Portable lift trucks are commonly utilized to move heavy articles, suchas appliances, barrels of bulk products, and pallets of materials, fromone location to another. It is frequently necessary to raise or lowerthe article being transported from one level to another. Most portablelift trucks, While being well adapted to facilitate the moving of anobject on one plane, are not suited for moving a heavy object from onelevel to another.

With known portable lift trucks it is necessary, when moving a load fromone level to another, to disconnect the load from the truck and to raiseor lower the load to the desired level. The process of raising orlowering the heavy load usually requires the combined efforts of severalmen or the use of hoists, jacks, and similar devices. Once the load hasbeen raised or lowered, it is often necessary to again connect the loa-dto the hand truck for additional movement. The time and effort which arewasted by disconnecting the load from a hand truck, raising the loadmanually or with separate hoisting equipment, and reconnecting the loadto the hand truck, will be readily apparent.

Therefore, one of the objects of this invention is to provide a portablelift truck which is well adapted for moving a load between two levelsand for moving the load on a given level.

Another object of this invention is to provide a portable lift truckwhich eliminates the necessity of disconnecting the truck from the loadwhen moving the load between two levels.

Another object of this invention is to provide a portable lift truckwhich eliminates the use of separate lifting machinery or manual effortto raise or lower a load.

For a fuller understanding of the nature and objects of the invention,reference should be had to the following description, taken inconnection with the accompanying drawings wherein:

FIG. l is an elevational view of the portable hydraulic lift truck;

FIG. 2 is a detail sectional view along the line 2-2 of FIG. 1;

FIG. 3 is a perspective view of the hydraulic lift truck being used toraise a load;

FIG. 4 is a perspective View of the portable hydraulic lift truckimmediately after raising the load; and

FIG. 5 is a schematic drawing of the hydraulic system utilized in thelift truck.

Referring now to the drawings in greater detail, the construction ofhydraulic lift truck is shown in FIGS. 1 and 2. The hydraulic lift truck10 has a load frame 12, an extension frame 14, and a hydraulic pumpmeans 16 to move the extension frame 14 relative to the load frame 12.When the hydraulic pump means 16 is actuated, the frame 14 will moverelative to the load frame 12 to raise or lower a load on frame 12.

Considering the load frame 12 in greater detail, two side members 18 and20 are connected at their lower end to a load engaging plate or bar 22.The two side members 18 and 20 are substantially parallel to each otherand, at the end of the side members opposite from the load plate or bar22, have handles 24 and 26 connected integrally with the side members.Bottom rail members 28 and 30 are connected to the upper end of the sidemembers 18 and 20 adjacent to the handles 24 and 26 (see FIG. 2). Thebottom rail members 28 and 30 are also connected to the side members 18and 20 by means of support members 32, 34, 36, 38, 40 and 42. Thesupport members 32 to 42 may be utilized as hand grips when moving thehydraulic lift truck from one position to another.

The hydarulic lift truck is supported by main wheels 44 and 46 which areconnected to a main axle 48. The main axle 48 is substantially parallelto the load plate or bar 22 and is supported from the side members 18and 20. When the lift truck is moved from one location to another, on agiven plane, the load is positioned on the load plate or bar 22 in theusual manner (see FIGS. 3 and 4) and the main wheels 44 and 46 arerolled along the surface while supporting the load carried by the lifttruck. When the lift truck is utilized to move a load along a singlehorizontal plane, the lift truck functions in the same manner as otherlift trucks presently in use. It should 'be noted that the load plate orbar 22 could, as will be apparent to those skilled in the art, bereplaced by a lift fork or other known load engaging devices. The loaditself is cradled between the two 'side members 18 and 20 and retainedthere by the strap 49 in a known manner. The load will rest against twocross members 50 and 152 which are connected between the two sidemembers 18 and 20 of the hydraulic lift truck.

The extension frame 14 includes a support bar 54 which is normallypositioned directly behind and substantially parallel to the load plateor bar 22 (see FIG. 2). Two parallel stabilizer bars 56 and 58 areconnected to opposite end portions of the support bar 54. The twostabilizer bars 56 and 58 slide telescopically in the hollow tubularside members 18 and 20 (see FIG. l). The suppo'rt bar 54 and the twostabilizer bars 56 and 58 are extended by the hydraulic means 16, fromthe position shown in FIG. 2 to the position shown in FIG. 3. The sidemembers 18 and 20 guide the movement of the stabilizer bars relative tothe load frame 12. The stabilizer bars 56 and 58 may be retractedtelescopically into the Side members 18 and Z0 by hydraulic means, whichwill be explained in greater detail later, to the position shown in FIG.2.

The hydraulic means 16 includes a pump 62 which is supported between thetwo side members 18 and 20 on a cross plate 60 near the upper portion ofthe lift truck. The cylinder member 64 is connected to the hydraulicpump 62 and is supported in a position intermediate, and parallel to,the side members 18 and 2li by the cross members 50 and 52. The rammember `65 is slidably positioned in the cylinder 64 and is connected tothe support bar 54 at connection 66 (see FIG. 1) between the twostabilizer bars 56 and 58.

The pump `62 is actuated by oscillating pump handle 68. Torsion bar 70transmits the oscillations of the pump handle 68 to a lever 72 and link74. The linkage 72 and 74 is connected to the pump piston by theconnection member 76. When the pump handle 68 is oscillated, theoscillation will cause the pump piston to pump hydraulic lluid underpressure into the cylinder 64. When the high pressure lluid enters intothe cylinder 64, the ram member 65 will be displaced outwardly from thecylinder 64 to extend the frame 14 relativemto the load frame 12. Itshould be noted that when the extension frame 14 is being moved relativeto the load frame 12 that the stabilizer bars 56 and 58 will maintainthe support bar 54 in a position which is substantially parallel to theload plate or bar 22.

The pump 62 has a Irelief or exhaust valve 78 to eX- haust the highpressure il'uid in the cylinder 64 to a relatively low pressurereservoir `80 (see FIG. 5) and to thereby permit the extension fra-me 14to be retracted back to the position shown in FIGS. 1 and 2. Theextension frame 14 is retracted back to the position shown in FIGS. 1and 2 by the action of two spring members 82 and 84 which are locatedwithin the stabilizer bars 56 and 58 and are connected to the supportbar 54 at connection points 86 and 88. The two springs 82 and 84 extendthe length of the stabilizer ba-rs 56 and 58 and are connected to theside members 18 and 20 at connection plugs 90 and 92 in the upper endsof the side members 18 and 20. It will be apparent that the springmembers `82 and 84 will cause the extension frame 14 to be retractedtelescopically back into the side members 18 and 20 whenever the reliefor exhaust valve 78 is positioned to exhaust the high pressure fluidwithin the cylinder 64 to the relatively low pressure reservoir 80.

The schematic drawing of the hydraulic circuit means for the lift truckis shown in FIG. 5 The exhaust or relief valve 78 connects the reservoir80, through hydraulic lines 94, 9S and 96, to the pump 62, and to thecylinder 64. The pump 62 is connected to the cylinder 64 by thehydraulic line 98.

The pump 62 can draw hydraulic fluid, from the reservoir 80, through thehydraulic line 94, valve 78 and line 96. When the valve 78 is in a rstposition high pressure hydraulic fluid, from the pump 62, will force theram member 65 to move the extension frame 14 outwardly relative to theload frame 12. When the relief or exhaust valve 78 is rotated to asecond or relief position, the reservoir `80 is connected to thecylinder 64 and the cylinder 64 will be in uid connection, through lines94 and 95, with the reservoir 80. With the valve 78 in the reliefposition the ram `member `65 will be forced telescopically into thecylinder 64, under the influence of the two spring members 82 and 84 toexhaust the hydraulic -uid from the cylinder to the reservoir 80.

In addition to the extension frame and hydraulic means, the load frame12 has connected thereto a pair of auxiliary wheels 100 and 102 whichare supported on an auxiliary wheel axle 104. The auxiliary wheel axle104 is connected to the main axle 48 for the main wheels 44 and 46 by`suspension bars 106 and 108. The suspension bars pivot about the mainaxle 48, as shown in FIG. 2. The auxiliary wheels 100 and 102 can pivotfrom a storage position, shown in dotted lines in FIG. 2, between thetwo side members 18 and 20 to a support position extending rearwardlyfrom the load frame, shown in solid lines in FIG. 2. The auxiliarywheels are normally held in the storage position by spring member 110which is coaxial with the main axle 48. The spring member 110 isconnected to the side member 20 at one end and to the suspension bar 108at the other end. While only one spring member 110 has been shown, itwill be apparent that a similar spring member could be connected to thesuspension bar 106 and the side member 18.

When the auxiliary wheels are pivoted from the storage position, shownin dotted lines in FIG. 2, to the stupport position, shown in solidlines in FIG. 2, a latch means 112 engages the end of the suspensionbars 106 and 108 to retain the auxiliary wheel in the support position.The latch means 112 includes a latch pawl 114 (and a similar latch pawlnot shown for the other suspension bar 108) which is supported on theaxle 116 for pivotal movement relative to the side members 18 and 20.The latch pawl 114 is normally pivoted forward to the position shown inFIG. 2 under the iniluence of spring 118.

When the auxiliary wheels are moved from the storage position to thesupport position, the rounded or cam surface 120 will cam the nose 122of the latch pawl 114 to the left of the position shown in FIG. 2 untilthe nose 122 of the latch pawl 114 clears the end of the suspension bar106. The nose 122 of the latch pawl 114 will then engage a notch 124 inthe suspension bar'106. When the 4 suspension bar 106 is engaged by thelatch pawl 114i, as shown in FIG. 2, the auxiliary wheels 100 and 102will be locked `against movement back to the storage position land willprovide support for the lift truck (see FIG. 4).

When the auxiliary wheels are to be returned to the storage position,the operator of the lift truck will actuate a latch release lever 126 bypressing on pad 12S at the end of the latch release lever 126. When thelatch release lever 126 is depressed, the lever will cause the pawl 114to swing to the left of the position shown in FIG. 2 and thereby releasethe suspension bar 106. The two latch pawls, for the suspension bars 106and 108 are interconnected -by connector bar 127. Thus the depression ofthe latch release lever 126 will release both latch pawls. Thesuspension bar 106 and the auxiliary wheels 100 and 102 will pivot whenthe latch release lever 126 is depressed, to the storage position underthe iniuence of the spring member 110. It will be apparent from FIG. 2that the latch release lever 126 and the pad 128 are positioned betweenthe two side members 18 and 20 where the latch release lever will not beaccidentally engaged while using the auxiliary support wheels to supportthe lift truck.

From the foregoing description of the auxiliary wheels, it will beapparent that the auxiliary wheels 100 and 102 may be utilized tosupport the lift truck in the upright position shown in FIG. 4. When itis desired to use the lift truck without the support of the auxiliarywheels, it is merely necessary to press the latch release lever and theauxiliary wheels will pivot to the storage position intermediate the twoside members 18 and 20. When the auxiliary wheels are in their storageposition the lift truck may be utilized in the normal manner. Theauxiliary wheels, in the storage position, will be out of the way andwill not interfere with the normal use of the lift truck. The mainwheels 44 and 46 provide the support for the lift truck when it is beingrolled along a horizontal surface. The auxiliary wheels 100 and 102 areutilized primarily to support the lift truck in an upright position, orto pivot the lift truck, when moving between levels, in a manner to beexplained more fully subsequently.

For the purpose of affording a more complete understanding of theinvention, it is advantageous to now provide a functional description 0fthe mode in which the component parts thus far identified cooperate. Itis apparent that with the auxiliary wheels in their storage position andthe extension frame retracted that the lift truck may be utilized in thesame manner in which prior art lift trucks are commonly used. When it isdesired to raise a load from a lower level, such as level 130 of FIG. 3to a higher level 132, the lift truck is irst positioned with the bottomrail members 28 and 30 contacting a corner 134l of the upper surface132. In this position the side members should be at approximately aifteen degree angle with the vertical. The relief or exhaust valve 78 ispositioned so that the uid from the reservoir 80 may be passed throughthe line 94, the valve 78, and the line 96 to the pump 62. The pumphandle 68 is oscillated to cause the pump to force the hydraulic iiuidunder pressure into the line 98 and the cylinder `64. The ram member 65will then force the load frame 12 and the load to move vertically upwardrelative to the support bar 54.

It should be noted that the support bar 54 is positioned with the angledlip 136 flat against the surface 130 (see FIG. 3). The continuedoscillation of the pump handle 68 will cause the load `frame to bedisplaced upward relative to the support bar 54 and ram `65. When theload frame has reached the position shown in FIG. 3, with the mainwheels 44 and 46 contacting the corner-134 of the upper surface 132, theauxiliary wheels 100 and 102 are pivoted, from the storage position, tothe support position, shown in solid lines in FIG. 2. The lift truck isthen rotated or pivoted around the axle 104 and the auxiliary wheels 100and 102. In this position the entire load of the lift truck is taken bythe auxiliary wheels 100 and 102. The truck is then pulled slightly backfrom the edge 134 of the surfacey 132 with the main wheels 44 and '46just above the surface 132. The lift truck is then rocked or pivotedforward to the position shown in FIG. 4. It should be remembered thatthe extension frame 14 is still extended and the lift truck cannot,therefore, 4be moved for a relatively large distance back from thecorner 134 of the surface 132. y

-Once the lift truck has been positioned as shown in FIG. 4, the reliefvalve 78 may be rotated to the relief position to connect thecylinder 64directly with the reservoir `80. The force of the two spring members 82and 84 on the support bar 54 will cause the extension frame to beretracted to the position adjacent the load engaging member 22 (shown insolid lines in FIG. 4). The lift truck may then be moved slightlyfurther back from the corner 134, and the auxiliary wheels 100 and 102retracted to their storage position intermediate the two side members 18and 20.

The procedure for lowering a load from the upper surface 132 to thelower surface 130 is merely a reversal of the previously set forthoperation for raising a load. Thus, when a load is to be lowered, thelift truck is moved to the edge of the surface with the auxiliary wheels100 and 102 locked in a supporting position. The lift truck is thenmoved slightly forward, supported by both the auxiliary wheels 100 and102 and the main wheels 44 and 46, so that the main wheels are adjacentthe edge' of the surface 132. The pump valve 78 is then positioned sothat the pump 62 is connected directly to the reservoir 80, so that thehigh pressure uid from the pump may be transmitted to the cylinder 64.The pump handle 68 is then rotated to cause the pump to move the rammember 65 downward relative to the load frame 12. It should be notedthat the extension frame 14 will just clear the corner 134 of thesurface 132.

When the support bar 54 has been placed with t-he angled lip 136 flatagainst the surface 130 (as shown in FIG. 3), the lift truck is thentilted slightly forward to take the weight of the load frame off boththe auxiliary wheels and the main wheels, and to place the weight ontothe support 'bar 54. The auxiliary Wheel members are then returned tothe storage position by actuating the latch release lever 126. The lifttruck will now appear substantially as shown in FIG. 3, with theexception :of the fact that the main wheels 44, 46 will be positionedslightly higher relative to the surface 132. rI'he relief or exhaustvalve 78 is then turned to exhaust the fluid from t-he cylinder 64 tothe reservoir 80. The weight of the load on the load frame of the lifttruck will cause the load to sink slowly to .the ground. The rate ofdescent of the load may be controlled by the gradual opening of therelief valve 78. The bottom rail members 28 and 30 will slide againstthe corner 134 while the load is descending. Thus the lift truckoperator will merely have to hold the upper end of the frame.

The lift truck may be easily manipulated when the load frame is beingtilted as the main wheels 44, 46 are moved to clear the corner 134during both the lifting and lowering operations. The manipulation of theload frame, while raising and lowering the load, is facilitated by thefact that the center of gravity of the load will be to the right (asseen in FIG. 3) of the support bar 54 and will thereby tend to stabilizethe Ilift truck when it is being manipulated. Thur, the weight of thelift truck and load will be supported in a -relatively stable positionby the bottom rail members 28 and 30 which will bear against the corner134 while the l-oad is being moved from one level to another.

From the foregoing description, it will be apparent that my novel lifttruck permits a single man to raise and lower a relatively 'heavy loadfrom one level to another without disconnecting the load from the lifttruck. The lift truck may be utilized as a standard lift truck with theauxiliary wheel members retracted to their storage position. Theauxiliary wheel members may also be placed in the support position toretain the lift truck in an upright position. In addition, the auxiliarywheels provide a fulcru-m around which the lift truck may be pivotedwhen positioning the lift truck relative to the edge of a surface forraising or lowering ra load. Since both the pump handle 68 and theauxiliary wheels may be placed in an unobtrusive storage position, thenormal hand operation of the lift truck is not in any way impeded 'bythe hydraulic lift means. The hydraulic lift means .is an integral partof the lift truck, and t'he necessity of positioning and maintainingauxiliary lifting equipment is eliminated when my portable hydrauliclift truck is utilized for moving load-s.

The specic example herein shown and described is considered to beprimarily illustrative. Various changes in the structure of the loadframe, extension frame and hydraulic means will, no doubt, occur tothose skilled in the art; and these changes are to be understood asforming a part of this invention insofar as they fall within the spiritand scope of the appended claims.

What is claimed is:

1. A portable lift truckV comprising a frame means for supporting aload, said frame means including a rst side member, a second side memberspaced apart from and substantially parallel to said first side member,a load engaging means, a lirst end portion of said load engaging meansconnected to an end portion of said rst side member, a second endportion of said load engaging means connected to an end portion of saidsecond side member, main wheel means mounted adjacent to said loadengaging means, auxiliary wheel means pivotally mounted adjacent saidm-ain wheel means, said auxiliary wheel means being pivotable from a rststorage position Ito a second position for supporting said frame means,and latch means to retain said auxiliary wheel means in said secondposition supporting said frame means; an extension means slidablyconnected to said frame means and movable relative to said frame means;and a hydraulic means mounted on said frame means and connected to saidextension means to move said frame means relative to said extensionmeans.

2. A lift tnuck as set forth in claim 1, wherein said main wheel meansincludes a main axle mounted adjacent said load engaging means, a iirstmain wheel mounted on a first end portion of said main axle, and asecond main wheel mounted on a second end portion of said axle; and saidauxiliary wheel means includes a first suspension -bar pivotably mountedon sai-d main axle, a second suspension ybar pivotally mounted on saidmain axle and spaced apart from and substantially parallel to said firstsuspension bar, a irst auxiliary wheel mounted adjacent an end portionof said iirst suspension bar, and a second auxiliary wheel mountedadjacent an end portion of said second suspension bar.

3. A lift truck as set forth in claim 2, whe-rein said latch meansincludes a rst latch pawl pivotally mounted adjacent said firstsuspension bar, a second latch pawl pivotably mounted adjacent saidsecond suspension bar and a latch pawl release means mounted adjacent tosaid rst land second latch pawls, said latch pawls being positioned toengage the adjacent suspension bar when said auxiliary wheel means ispivoted to said second supporting position and said latch pawl releasemeans 'being adapted to move said rst and second latch pawls to releasesaid suspension bars when said latch pawl release means is actuated toenable said auxiliary wheel means to pivot to said first storageposition.

4. A portable lift truck comprising a frame means for supporting a load,an extension means slidably connected to said frame means and movablerelative to said frame means, said extension means including a supportbar, a iirst stabilizer member connected to said support ybar and guidedby said fra-me means for sliding movement relative to said frame means,:a second stabilizer member connected to said support bar spaced apartfrom and substantially parallel to said first stabilizer member, saidsecond stabilizer member being guided by said frame means for slidingmovement relative to said frame means; and a hydraulic means mounted onsaid frame means and connected to said extension -means to move saidframe means relative to said extension means, said hydraulic meansincluding a fluid reservoir, pump means mounted on said frame means andconnected to said fluid reservoir, cylinder means connected to said pumpmeans and spaced apart from and substantially parallel to said first andsecond stabilizer members, valve means connected to said pump means andsaid fluid reservoir to control the flow of Ihigh pressure fiuid fromsa-id pump means to said cylinder means, said valve means being movableto a first position to conduct fluid from Isaid pump means to saidcylinder means and to a second position to conduct diuid Ifrom saidcylinder means to said rese-rvoir, and ram means, a first end portion ofsaid ram means being connected to said support bar, and the second endportion of said ram means being positioned in said cylinder means :andguided by said cylinder means for sliding movement relative to saidcylinder means, said hydraulic pump means supplying fluid to saidcylinder means to displace said ram means relative to said cylindermeans.

5. A lift truck as set forth in claim 4, wherein said extension meansincludes spring means connected to said support bar and said frame meansto move said support bar to a position adjacent said frame means whensaid valve means is in said second position.

6. A portable lift truck comprising a frame means for supporting laload, said frame means including a first side member, a second sidemember spaced apart from and substantially parallel to said first sidemember, a load engaging means, a first end portion of said load engagingmeans connected to said first first side member, and a second endportion of said load engaging means connected to said second sidemember; said extension means includes a support bar positionedsubstantially parallel to said load engaging means, a first stabilizermember connected to said support bar and guided by said first sidemember for sliding movement relative to said frame means, and a secondstabilizer member connected to said support bar and guided by saidsecond side member for sliding movement relative to said frame means; anextension means slidably connected to said frame means and movablerelative to said frame means; and a hydraulic means mounted on saidframe means and connected to said extension means to move said framemeans relative to said extension means, said hydraulic means including aiiuid reservoir, pump means mounted on said frame means and connected tosaid fiuid reservoir, cylinder means connected to said pump :means andspaced apart from and substantially parallel to said` first and secondside members, valve means connected to said pump means and said fiuidreservoir to control the fiow of fluid from said pump means to saidcylinder means, said valve means being movable to a fi-rst position toconduct fiuid from said pump means to said cylinder means and to asecond position to conduct fluid from said cylinder means to saidreservoir, and ram means, a first end portion of said ram means beingconnected to said support bar and a second end portion of said ram meansbeing positioned `within said cylinder means and guided by said cylindermeans for sliding movement relative to said cylinder means, said rammeans being displaced relative to said cylinder means by fluid from saidpump means when said valve means is in said first position.

7. A lift truck as set forth in claim 6, wherein said extension meansfurther includes spring means connected to said support bar and saidframe means to move said support -bar to a position adjacent said springmeans when said valve means is in said second position.

8. A lift truck as set forth in claim 6, wherein said frame meansfurther includes main wheel means mounted adjacent to said load engagingmeans, auxiliary wheel means pivot-ally mounted adjacent said main wheelmeans, said auxiliary wheel means being pivotal from a first storageposition intermediate said first and second side lmembers to a secondposition for supporting said frame means, and latch means to retain saidauxiliary wheel means in said second position.

9. A lift truck as set forth in claim S, wherein said main wheel meansincludes a main axle mounted adjacent said load engaging means, a firstmain wheel mounted on a first end portion of said main axle, and a'second main wheel mounted on a second end portion of said main axle; andsaid auxiliary wheel means inculdes a first suspension bar pivotallymounted on said main axle, a second suspension bar pivotally mounted onsaid main axle spaced apart from and substantially parallel to saidfirst suspension bar, a first auxiliary wheel mounted adjacent an endportion of said first suspension bar, and a second auxiliary wheelmounted adjacent said second suspension bar; and said latch meansincludes a first latch pawl pivotally mounted adjacent said firstsuspension bar, a second latch pawl pivotally mounted adjacent saidsecond suspension bar, and a latch paw! release means mounted adjacent'to said first and second latch pawls, said latch pawls being positionedto lock the adjacent suspension bar when said auxiliary wheel means ispivoted to said second position and to release said adjacent suspensionbar when said latch pawl release means is actuated to enable saidauxiliary wheel means to pivot to said first storage position.

References Cited UNITED ST ATES PATENTS 2,192,396 3/ 1940 Burch.

2,608,258 8/1952V Jenkins 280-5.3 X 2,616,720 11/1952 Knoth 280--5-3 X2,740,637 4/1956 Cononelos ZBO-5.3 2,834,602 5/1958 Hanson 28o- 5.33,053,546 9/1962 Muirhead 280-5,3

LEO FRIAGLIA,A Primary Examiner.

1. A PORTABLE LIFT TRUCK COMPRISING A FRAME MEANS FOR SUPPORTING A LOAD,SAID FRAME MEANS INCLUDING A FIRST SIDE MEMBER, A SECOND SIDE MEMBERSPACED APART FROM AND SUBSTANTIALLY PARALLEL TO SAID FIRST SIDE MEMBER,A LOAD ENGAGING MEANS, A FIRST END PORTION OF SAID LOAD ENGAGING MEANSCONNECTED TO AN END PORTION OF SAID FIRST SIDE MEMBER, A SECOND ENDPORTION OF SAID LOAD ENGAGING MEANS CONNECTED TO AN END PORTION OF SAIDSECOND SIDE MEMBER, MAIN WHEEL MEANS MOUNTED ADJACENT TO SAID LOADENGAGING MEANS, AUXILIARY WHEEL MEANS PIVOTALLY MOUNTED ADJACENT SAIDMAIN WHEEL MEANS, SAID AUXILIARY WHEEL MEANS BEING PIVOTABLE FROM AFIRST STORAGE POSITION TO A SECOND POSITION FOR SUPPORTING SAID FRAMEMEANS, AND LATCH MEANS TO RETAIN SAID AUXILIARY WHEEL MEANS IN SAIDSECOND POSITION SUPPORTING SAID FRAME MEANS; AN EXTENSION MEANS SLIDABLYCONNECTED TO SAID FRAME MEANS AND MOVABLE RELATIVE TO SAID FRAME MEANS;AND A HYDRAULIC MEANS MOUNTED ON SAID FRAME MEANS AND CONNECTED TO SAIDEXTENSION MEANS TO MOVE SAID FRAME MEANS RELATIVE TO SAID EXTENSIONMEANS.